The present invention is related to a container with a cover constructed to allow complete drainage of the container contents, and thus reduce drainage residue.
The complete drainage of containers is very important for many reasons. Due to the increasing usage of containers as multi-use vessels, ever greater amounts of drainage residues are produced. Chemical and pharmaceutical manufacturers and researchers use expensive reagents and chemicals delivered in containers. Because the containers do not allow near-complete emptying, research and production costs increase as it is necessary to purchase more reagent chemicals to replace the residue. When hazardous materials are used, residues, brought about by containers that do not allow complete emptying, have a detrimental effect on the environment as they are simply thrown away as waste, which accumulates as more material is purchased to make up for the residue. For example, residue in a 50-gallon drum that does not allow near-complete emptying can total about 500-700 cc of the fluid material.
The steps previously taken to solve this problem have not been satisfactory. With existing designs, in order to obtain residual fluid through the fill and drainage bung of the container, the user must resort to turning the container upside down and moving it back and forth to try to get the residual fluid into the aperture of the bung. However, it is not possible to obtain an adequate drainage of residue in this manner.
According to one previous design, U.S. Pat. No. 4,767,021, a barrel having a specially designed top head has been developed, in which the residual fluid is collected and guided to the aperture of the bung. For this purpose, a segmented portion of the upper end of the barrel is indented and sloped inward to the body of the barrel. When the barrel is tipped upside down, the residual liquid flows on the inside of the flattened portion towards the barrel wall to the bung housing and out of the barrel through the bung socket. Even though appreciable improvements have been achieved, additional handling of the container is still required and a very complex cover must be provided.
U.S. Pat. No. 4,767,021 at FIG. 5 shows an embodiment of a drum design with one bung. However, in a drum design containing only one bung, there is a splashing effect during the outpouring of the fluid from the container, caused by the displacement of air in the container. The splashing effect prevents all the fluid from being transferred to another holder, container, or medium, but rather an amount of the fluid material falls on surfaces in the surrounding area. This leads to a waste of fluid material, which can be an environmental hazard (if the fluid material is hazardous), and drive up expenses (as additional fluid material may have to be purchased).
Accordingly, it is an object of this invention to provide a container which solves the problems of the prior art.
It is another object of the present invention to provide a container that allows approximately complete emptying of the container with a relatively simple cover shape.
It is yet another object of this invention to avoid additional manipulation of a container in an effort to completely empty the container once it has been inverted.
It is a further object of this invention to provide a container which reduces environmental pollution by reducing the amount of residue left in the container after emptying.
It is a still further an object of this invention to reduce the cost of reagents used in research by allowing researchers to use approximately all of the fluid material.
It is yet a further object of this invention to reduce the amount of splashing associated with pouring fluid material from a container with one bung.
Pursuant to the present invention, these objects are accomplished by providing a container having a bung which is arranged on the cover or lid portion of the container at a position adjacent the rim of the wall of the container, either adjoined to the rim or immediately adjacent thereto with only a relatively small space therebetween. Furthermore, the cover of the container is designed such that, when the drum is inverted, the bung is at a level which is lower than any other point on the cover.
The cover may intersect with the side walls on a horizontal plane as is conventional, or it may intersect at a slight angle such that in an inverted drum the bung is at the edge of the cover which is farthest down.
The cover is designed with a crease extending from the bung across the center of the lid to the opposite side. In the embodiment in which the intersection of the lid with the container is on a horizontal plane, the lid will achieve the shape of an offset dome with the high point (when the container is upright) at the aperture of the bung very near to the side wall. Thus, there will be a sharp angle to the bung in the very small space between the bung and the wall, with a very gentle slope from the remainder of the points of intersection of the cover with the side walls to the aperture of the bung. The slight crease in the lid along the diameter from the bung to the opposite side further aids in channeling the liquid within the container to the bung when the container is tipped or inverted.
In the embodiment in which the plane of intersection of the cover with the drum is sloped, the bung may be adjoined to the rim. There is still preferably a slight dome-shaped element leading to the aperture of the bung so that a crease can also be placed in the cover along the diameter from the bung to the opposite side, as described above for the first embodiment.
In order to further conserve the liquid stored within the container, and protect the user from its potential toxicity or caustic properties, a device is provided to prevent the splashing of liquid as air is forced to enter the bung upon pouring of the liquid from the container. For this purpose, a small pipe or tube is placed in the bung aperture which extends to a point at the bottom of the container which is diagonally opposite the edge of the container at which the bung is located. Preferably, the pipe or tube extends from the side of the bung aperture farthest from the rim, along the ridge to the point at the underside of the cover which adjoins the wall of the container opposite the position of the bung, and then proceeds directly downwardly along the inner side wall of the container to a point substantially adjacent the floor of the container, while being spaced therefrom far enough to avoid occlusion of the opening of the pipe or tube by the floor of the container. In this way, when the container is being tilted to pour liquid out of the bung aperture, particularly when being tilted more than 90xc2x0 from the vertical, air will enter the tube and replace the liquid, thus avoiding the gurgling that would normally occur. In another embodiment, the device for preventing splashing is a short tube placed inside the bung aperture, directed to the area of the intersection of the cover with the side wall furthest from the bung. In this way, when the container is full and begins to pour, particularly as it is tilted from the vertical up to an angle of 90xc2x0, air is allowed to flow through the short tube into the upper portion of the container, thus preventing gurgling. In yet another embodiment, both a long tube and a short tube may be present, the long tube being directed to a point substantially adjacent to the floor of the container diagonally opposite the bung, and the short tube directed to the area of the intersection of the cover with the side wall diametrically opposite the bung. In this way, when the container is full and begins to pour, until it reaches an angle of 90xc2x0 from the vertical, air will flow through the short tube to the area at the top of the container from which liquid is being displaced, thus preventing gurgling, and when the tilt is greater than 90xc2x0 from the vertical, air is allowed to enter the long tube and replace the liquid being displaced from the bottom of the container, which is now uppermost, thus avoiding the gurgling that would normally occur.